CN108730237B - Fan silencer capable of measuring flow - Google Patents
Fan silencer capable of measuring flow Download PDFInfo
- Publication number
- CN108730237B CN108730237B CN201810433002.8A CN201810433002A CN108730237B CN 108730237 B CN108730237 B CN 108730237B CN 201810433002 A CN201810433002 A CN 201810433002A CN 108730237 B CN108730237 B CN 108730237B
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- Prior art keywords
- pressure measuring
- fan
- pipe
- shell
- measuring point
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/661—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
- F04D29/663—Sound attenuation
- F04D29/664—Sound attenuation by means of sound absorbing material
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/001—Testing thereof; Determination or simulation of flow characteristics; Stall or surge detection, e.g. condition monitoring
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/661—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
- F04D29/663—Sound attenuation
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
- Measuring Volume Flow (AREA)
Abstract
The invention belongs to the technical field related to fan noise elimination equipment, and discloses a fan muffler capable of measuring flow, which comprises a shell and two pressure measuring connecting pipes, wherein an accommodating cavity is formed in the shell, and an air channel is arranged in the accommodating cavity; the fan silencer also comprises a sound absorption material, and the sound absorption material is filled between the air duct and the shell; the air channel is provided with at least one first pressure measuring point and at least one second pressure measuring point, and the first pressure measuring point and the second pressure measuring point are arranged at intervals; the two pressure measuring connecting pipes are respectively arranged on the shell and are respectively communicated with the first pressure measuring point and the second pressure measuring point, so that the flow of the fan is obtained according to the detected pressure by detecting the pressure at two points of the air channel. The fan silencer organically combines the noise elimination function with flow measurement, and is simple in structure, small in pressure loss and good in noise reduction effect.
Description
Technical Field
The invention belongs to the technical field of fan noise elimination equipment, and particularly relates to a fan noise eliminator capable of measuring flow.
Background
The silencer is an airflow pipeline with noise transmission, and can adopt a pipeline and an elbow with sound absorption linings or noise reduction devices such as pipelines with changed sectional areas and other discontinuous acoustic impedances and the like, so that noise in the pipeline is attenuated or reflected back, the former becomes a resistive silencer, and the latter becomes a resistive silencer. The resistive muffler mainly eliminates medium-high frequency noise, and the reactive muffler mainly eliminates low-frequency or medium-low frequency noise. If only one of the silencing principles is adopted, the range of noise which can be eliminated is narrow as a result.
At present, some researches have been made by those skilled in the art, for example, patent CN 202117739U discloses an impedance composite muffling structure, which has a better muffling effect but only has a muffling effect. However, in practical application, the flow of the fan is often required to be measured, but the flow measurement needs a long straight pipe section, and general field conditions are difficult to meet. Accordingly, there is a need in the art to develop a fan silencer that can measure flow.
Disclosure of Invention
Aiming at the defects or improvement requirements of the prior art, the invention provides the fan silencer capable of measuring the flow, which is based on the working principle of the silencer and is researched and designed to simultaneously measure the flow while eliminating the noise. The cross sections of the air channels of the fan silencer, which are perpendicular to the length direction of the shell, are not identical in size, wherein the flow guide structure is conical, the throat pipe is formed in the middle of the central pipe, and the silencing cavity is formed in the middle of the silencing pipe, so that the cross sections of the air channels are changed, and because each pipeline only allows noise in a certain frequency range to pass through, medium and low frequency noise in a large frequency range can be eliminated, and the silencing effect is improved. In addition, the sound absorption material is filled between the air duct and the shell, so that medium-high frequency noise is eliminated by adopting a resistive noise elimination principle, and the sound absorption material is combined with an air duct structure to realize the elimination of noise in a larger frequency range.
In order to achieve the above object, according to one aspect of the present invention, there is provided a fan silencer capable of measuring flow, the fan silencer includes a housing and two pressure measuring connection pipes, the housing forms an accommodation cavity, an air duct is disposed in the accommodation cavity, and the sizes of cross sections of the air duct perpendicular to the length direction of the housing are not completely the same; the fan silencer also comprises a sound absorption material, and the sound absorption material is filled between the air duct and the shell;
the air channel is provided with at least one first pressure measuring point and at least one second pressure measuring point, and the first pressure measuring point and the second pressure measuring point are arranged at intervals; the two pressure measuring connecting pipes are respectively arranged on the shell and are respectively communicated with the first pressure measuring point and the second pressure measuring point, so that the flow of the fan is obtained according to the detected pressure by detecting the pressure at two points of the air channel.
Furthermore, at least one first pressure measuring point is positioned on the same plane and communicated with each other; at least one second pressure measuring point is coplanar and is communicated with each other.
Further, the fan silencer further comprises a central pipe, a plurality of silencing pipes and two flow guide structures, two ends of each silencing pipe are connected to the two flow guide structures respectively, and two ends of the central pipe are connected to the two flow guide structures respectively, so that the air duct is formed.
Furthermore, both ends of the shell are respectively provided with an air inlet and an air outlet, and the two flow guide structures are respectively connected to the air inlet and the air outlet.
Furthermore, the flow guide structure is conical and comprises a conical pipe and a plurality of connecting pipes, one end of each connecting pipe is connected to the conical pipe, and the plurality of connecting pipes are arranged around the central shaft of the conical pipe in a scattering manner.
Further, the other ends of the connecting pipes are respectively connected to the central pipe and the silencing pipe; the two conical pipes of the flow guide structure are respectively connected to the air inlet and the air outlet.
Further, the shell and the central tube are both cylindrical, and the central axis of the shell coincides with the central axis of the shell.
Furthermore, a throat pipe is formed in the middle of the central pipe, and the throat pipe is waist-drum-shaped.
Furthermore, a silencing cavity is formed in the middle of the silencing tube, and the position of the silencing cavity corresponds to the position of the throat tube.
Further, a plurality of the muffler pipes are evenly arranged around the central pipe, and the plurality of the muffler pipes are equal to the central pipe in distance.
Generally, compared with the prior art, the fan silencer capable of measuring flow rate provided by the invention has the following beneficial effects:
1. the sizes of the cross sections of the air channels perpendicular to the length direction of the shell are not completely the same, wherein the flow guide structure is conical, the throat pipe is formed in the middle of the central pipe, and the silencing cavity is formed in the middle of the silencing pipe, so that the change of the cross sections of the air channels is realized, and because each pipeline only allows noise in a certain frequency range to pass through, the medium-low frequency noise in a larger frequency range can be eliminated, and the silencing effect is improved.
2. The sound absorption material is filled between the air duct and the shell, so that medium-high frequency noise is eliminated by adopting a resistive noise elimination principle, and the sound absorption material is combined with an air duct structure to eliminate noise in a larger frequency range.
3. The air duct is provided with at least one first pressure measuring point and at least one second pressure measuring point, the flow of the fan is obtained according to the detected pressure by detecting the pressure at two points of the air duct, so that the total air volume is calculated by measuring the air volume of the central tube which only occupies a very small part of the total air volume, the problem of large pressure loss in the conventional direct measurement process of the total air volume is solved, the flow guide structures at two ends of the central tube not only reduce airflow resistance, but also indirectly prolong the length of the straight tube section of the central tube, meet the requirements on the length of the front straight tube section and the rear straight tube section in air volume measurement, and enable the measurement result to be more accurate.
4. The fan silencer organically combines the noise elimination function with flow measurement, and has the advantages of simple structure, small pressure loss, good noise reduction effect, high integration level and accurate flow measurement.
Drawings
FIG. 1 is a cross-sectional view of a fan muffler with a measurable flow rate provided by the present invention.
FIG. 2 is a cross-sectional view of the fan muffler of FIG. 1 with flow rate measurement taken in the direction 2-2.
FIG. 3 is a cross-sectional view of the fan muffler of FIG. 1 with flow rate measurement taken in the direction 3-3.
FIG. 4 is a cross-sectional view of the fan muffler of FIG. 1 with flow rate measurement taken in the direction 4-4.
The same reference numbers will be used throughout the drawings to refer to the same or like elements or structures, wherein: 1-an air inlet flange, 2-a sound absorption material, 3-a flow guide structure, 4-a first pressure measuring point, 5-an anechoic tube, 6-a pressure measuring connecting tube, 7-an anechoic cavity, 8-a second measuring point, 9-a central tube and 10-an outlet flange.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
Referring to fig. 1, 2, 3 and 4, the fan silencer capable of measuring flow rate according to the present invention adopts an impedance composite noise elimination principle, and absorbs medium and low frequency noise by using a change of a duct cross section, and absorbs medium and high frequency noise by using a sound absorption material; in addition, the air quantity is measured through pressure measuring points on a central pipe forming the air duct, the silencer of the fan organically combines the noise elimination function with the air quantity measurement, the integration level is improved, the structure is compact and simple, the pressure loss is small, the noise reduction effect is good, and the air quantity measurement is accurate.
The fan silencer comprises a shell, an air inlet flange 1, an air outlet flange 10 and two pressure measuring connecting pipes 6, wherein the shell is basically cylindrical, an air inlet and an air outlet are formed in two ends of the shell respectively, the air inlet flange 1 is connected to the air inlet, and the air outlet flange 10 is connected to the air outlet. The fan silencer is connected to a part to be silenced through the air inlet flange 1 and the air outlet flange 10. An accommodating cavity is formed in the shell and communicated with the air inlet and the air outlet.
The fan silencer further comprises a central pipe 9, a plurality of silencing pipes 5 and two flow guide structures 3, wherein the central pipe 9, the silencing pipes 5 and the flow guide structures 3 are contained in the containing cavity. The two ends of the muffling tube 5 are respectively connected to the two flow guide structures 3, and the two ends of the central tube 9 are also respectively connected to the two flow guide structures 3, so that an air duct is formed.
The central tube 9 is located in the middle of the muffling tubes 5, and the two flow guide structures 3 are respectively connected to the air inlet and the air outlet. In this embodiment, the central tube 9, the muffling tube 5, the flow guiding structure 3, the air inlet and the air outlet are all communicated.
The flow guiding structure 3 is substantially conical and comprises a conical tube and a plurality of connecting tubes, one end of each connecting tube is connected to the conical tube, and the connecting tubes are arranged around the central axis of the conical tube in a scattering manner. The other ends of the plurality of connection pipes are connected to the center pipe 9 and the muffler pipe 5, respectively. The two conical pipes of the flow guide structure 3 are respectively connected to the air inlet and the air outlet, and the two conical pipes are respectively used for flow guide. Therefore, the inner diameter of the air duct from the air inlet to one end of the central tube 9 is gradually increased, and the inner diameter of the air duct from the air outlet to one end of the central tube 9 is also gradually increased.
The central axis of the central tube 9 coincides with the central axis of the shell, and a throat is formed in the middle of the central tube and is waist-drum-shaped. The silencing tubes 5 are uniformly distributed around the central tube 9, and the distance between each silencing tube 5 and the central tube 9 is equal. In this embodiment, the middle of the muffling tube 5 is formed with a muffling cavity 7, and the muffling cavity 7 is substantially in a shape of a stepped cylinder. In this embodiment, the geometric center of the throat, the geometric center of the muffling cavity 7 and the geometric center of the shell are located in the same plane; the position of the throat pipe corresponds to the position of the anechoic cavity 7; the number of the muffling tubes 5 is 4, 6 or 8.
The inlet section of the central tube 9 is provided with a first pressure measuring point 4, and the wall surface of the throat is provided with a second pressure measuring point 8. In this embodiment, the number of the first pressure measuring points 4 and the number of the second pressure measuring points 8 are at least one, and at least one first pressure measuring point 4 is located on the same plane and is communicated with each other through the pressure measuring connecting pipe 6; at least one second pressure measuring point 8 is coplanar and communicated with each other through another pressure measuring connecting pipe 6.
The two pressure measuring connecting pipes 6 are arranged on the shell and are respectively communicated with the first pressure measuring point 4 and the second pressure measuring point 8 so as to measure the pressure at two points, and then the flow is calculated according to the pressure value obtained by the test. It is understood that, in other embodiments, the blower muffler may further include a microprocessor connected to the pressure measuring connection pipe 6, and configured to receive the detected pressure value and calculate the flow rate according to the pressure value.
In particular, the pressure at two points of the central tube 9 is measured, and according to the bernoulli principle and the continuity equation, the flow rate can be expressed as:
wherein, P1Pressure in the inlet section of the central tube, P2Pressure at the throat, ρ is the density of the gas flow, S1Is the cross-sectional area, S, of the inlet section of the central tube2Is the cross-sectional area of the throat, S3the sectional area of the inlet section of the muffler pipe, n is the number of the muffler pipes, α is a correction coefficient which depends on specific working conditions and measurement resultsAnd (6) correcting.
In the present embodiment, the inner diameter of the center tube 9 varies with its length; the inner diameter of the muffling tube 5 also varies with its length, and the noise is attenuated by the reactive muffling. And a sound absorption material 2 is filled between the air duct and the shell, namely the sound absorption material 2 is filled among the muffler pipe 5, the central pipe 9, the flow guide structure 3 and the shell. Therefore, the resistive noise elimination principle is adopted to convert sound energy into heat energy to be eliminated, and medium-high frequency noise is eliminated. In this embodiment, the sound absorbing material 2 may be hard fiber or asbestos.
In this embodiment, the length of the housing is 3 to 4 times the inner diameter thereof; the inner diameter of the air inlet is 0.5-2/3 times of the inner diameter of the shell; the length of the flow guide structure 3 along the central shaft is 0.2-0.25 times of the length of the shell; the sizes of the two conical pipes correspond to the size of the air inlet and the size of the air outlet respectively, and the sizes of the connecting pipes correspond to the sizes of the silencing pipes and the size of the central pipe 9; the inner diameter of the inlet section of the central tube 9 is 1/4 to 1/3 times of the inner diameter of the shell; the inner diameter of the throat pipe is 1/2 to 2/3 times of the inner diameter of the inlet section of the central pipe 9; the length of the inlet section of the central tube 9 is equal to that of the outlet section of the central tube 9, and the lengths are respectively 4-5 times of the inner diameter of the central tube 9; the distance between the central axis of the silencing pipe 5 and the central axis of the central pipe 9 is 1/4 to 1/3 times of the inner diameter of the shell; the inner diameter of the silencing pipe 5 is 2/3-1 times of the inner diameter of the inlet section of the central pipe 9; the diameter of the silencing cavity is 3/2-2 times of the inner diameter of the silencing tube 5; the length of the anechoic cavity is 1-3/2 times of the diameter of the anechoic cavity.
According to the fan silencer capable of measuring the flow, provided by the invention, the sizes of the cross sections of the air channels of the fan silencer, which are vertical to the length direction of the shell, are not completely the same; the flow guide structure is conical, the throat pipe is formed in the middle of the central pipe, the silencing cavity is formed in the middle of the silencing pipe, so that the cross sections of the air channels are changed, and because each pipeline only allows noise in a certain frequency range to pass through, medium and low frequency noise in a large frequency range can be eliminated, and the silencing effect is improved. In addition, the sound absorption material is filled between the air duct and the shell, so that medium-high frequency noise is eliminated by adopting a resistive noise elimination principle, and the sound absorption material is combined with an air duct structure to realize the elimination of noise in a larger frequency range.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (8)
1. The utility model provides a fan silencer of measurable flow which characterized in that:
the fan silencer comprises a shell and two pressure measuring connecting pipes, wherein an accommodating cavity is formed in the shell, an air channel is arranged in the accommodating cavity, and the sizes of the cross sections, perpendicular to the length direction of the shell, of the air channels are not completely the same; the fan silencer also comprises a sound absorption material, and the sound absorption material is filled between the air duct and the shell;
the air channel is provided with at least one first pressure measuring point and at least one second pressure measuring point, and the first pressure measuring point and the second pressure measuring point are arranged at intervals; the two pressure measuring connecting pipes are respectively arranged on the shell and are respectively communicated with the first pressure measuring point and the second pressure measuring point, so that the flow of the fan is obtained according to the detected pressure by detecting the pressure at two points of the air channel;
the fan silencer further comprises a central pipe, a plurality of silencing pipes and two flow guide structures, wherein two ends of each silencing pipe are respectively connected to the two flow guide structures, and two ends of the central pipe are also respectively connected to the two flow guide structures, so that the air duct is formed; a throat is formed in the middle of the central tube, the first pressure measuring point is arranged at the inlet section of the central tube, and the second pressure measuring point is arranged on the wall surface of the throat; wherein the inner diameter of the throat is 1/2 to 2/3 times of the inner diameter of the inlet section of the central tube 9;
the silencing pipes are uniformly distributed around the central pipe, and the distance between the silencing pipes and the central pipe is equal.
2. The fan muffler with flow measurement according to claim 1, wherein: the number of the first pressure measuring points is more than 1, and the first pressure measuring points are positioned on the same plane and are communicated with one another; the number of the second pressure measuring points is more than 1, and the second pressure measuring points are coplanar and are communicated with each other.
3. The fan muffler with flow measurement according to claim 1, wherein: the two ends of the shell are respectively provided with an air inlet and an air outlet, and the two flow guide structures are respectively connected to the air inlet and the air outlet.
4. The fan muffler with flow measurement according to claim 3, wherein: the water conservancy diversion structure is the toper, and it includes conical duct and a plurality of connecting pipe, and is a plurality of the one end of connecting pipe connect in the conical duct, and it is a plurality of the connecting pipe is around the center pin of conical duct is the setting of scattering form.
5. The fan muffler with flow measurement according to claim 4, wherein: the other ends of the connecting pipes are respectively connected with the central pipe and the silencing pipe; the two conical pipes of the flow guide structure are respectively connected to the air inlet and the air outlet.
6. The fan muffler with flow measurement according to claim 1, wherein: the shell and the central tube are both cylindrical, and the central axis of the shell coincides with that of the central tube.
7. The fan muffler with flow measurement according to claim 1, wherein: a throat pipe is formed in the middle of the central pipe and is in a waist drum shape.
8. The fan muffler with flow measurement according to claim 7, wherein: and a silencing cavity is formed in the middle of the silencing pipe, and the position of the silencing cavity corresponds to that of the throat pipe.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810433002.8A CN108730237B (en) | 2018-05-08 | 2018-05-08 | Fan silencer capable of measuring flow |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810433002.8A CN108730237B (en) | 2018-05-08 | 2018-05-08 | Fan silencer capable of measuring flow |
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| Publication Number | Publication Date |
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| CN108730237A CN108730237A (en) | 2018-11-02 |
| CN108730237B true CN108730237B (en) | 2020-05-19 |
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| CN201810433002.8A Expired - Fee Related CN108730237B (en) | 2018-05-08 | 2018-05-08 | Fan silencer capable of measuring flow |
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Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107044448A (en) * | 2016-02-05 | 2017-08-15 | 开利公司 | Muffler, the centrifugal compressor with it and refrigeration system |
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| JP2008064692A (en) * | 2006-09-08 | 2008-03-21 | Mitsuba Corp | Method and device for surveying sound source |
| CN201218382Y (en) * | 2008-05-30 | 2009-04-08 | 四川正升环保科技有限公司 | Resistance silencer |
| CN101435441A (en) * | 2008-12-03 | 2009-05-20 | 中国矿业大学 | Mining blower silencer |
| CN201306317Y (en) * | 2008-12-03 | 2009-09-09 | 中国矿业大学 | Air compressor silencer for mines |
| CN102536916A (en) * | 2010-12-09 | 2012-07-04 | 贵州省鼓风机厂 | High-flow ventilator silencer and manufacturing method thereof |
| CN204188208U (en) * | 2014-09-18 | 2015-03-04 | 国家电网公司 | A kind of coal-burning boiler apparatus for measuring air quantity |
| CN105952687A (en) * | 2016-03-17 | 2016-09-21 | 潘泉方 | Fan silencer |
-
2018
- 2018-05-08 CN CN201810433002.8A patent/CN108730237B/en not_active Expired - Fee Related
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008064692A (en) * | 2006-09-08 | 2008-03-21 | Mitsuba Corp | Method and device for surveying sound source |
| CN201218382Y (en) * | 2008-05-30 | 2009-04-08 | 四川正升环保科技有限公司 | Resistance silencer |
| CN101435441A (en) * | 2008-12-03 | 2009-05-20 | 中国矿业大学 | Mining blower silencer |
| CN201306317Y (en) * | 2008-12-03 | 2009-09-09 | 中国矿业大学 | Air compressor silencer for mines |
| CN102536916A (en) * | 2010-12-09 | 2012-07-04 | 贵州省鼓风机厂 | High-flow ventilator silencer and manufacturing method thereof |
| CN204188208U (en) * | 2014-09-18 | 2015-03-04 | 国家电网公司 | A kind of coal-burning boiler apparatus for measuring air quantity |
| CN105952687A (en) * | 2016-03-17 | 2016-09-21 | 潘泉方 | Fan silencer |
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Granted publication date: 20200519 Termination date: 20210508 |